1. Field of the Invention
The present invention relates generally to hydromassage bath systems and more particularly, to such systems wherein air is expelled from a plurality of jets mounted on the wall of a bathtub for activating the water into a massaging action on the user therein.
2. Prior Art
The use of a hydromassage as a means for relieving fatigued muscles and soothing the aches and pains of physical injuries is certainly well-known in the prior art. Most hydromassage systems known in the United States are of the type which employ a plurality of venturi jets which mix air and water utilizing a high speed flow of water to suction air into the mixture. An altogether different type of hydromassage system has become popular, primarily in Europe and this European system relies entirely on the injection of air such as into a bath full of water. One of the advantages of a system which uses only air is that it tends to be simpler and less costly to manufacture and therefore more readily available to the general public at lower cost while still providing beneficial hydromassage effects. Typical air injection systems force air through a plurality of exit ports mounted within a tub to activate the water and massage the user. Because of the differences in the behavior of air bubbles injected into a bathtub full of water as compared to a mixture of air and water and particularly, high pressure water, it is preferable in air injection systems to use a large plurality of injection ports preferably at the bottom of the tub as opposed to the side walls of the tub. Unfortunately, the process of connecting an air hose to each of a plurality of inlet ports at the bottom of a tub can become quite complex and expensive thereby defeating the otherwise advantageous simplicity of using only air instead of a combination of air and water. For example, one prior art air injection system uses an air manifold in which a separate parallel pipe connection is provided to each of a large plurality of air injector ports. Another prior art system requires placing an inner tub surface inside the existing tub surface in order to facilitate installation of a plurality of jets between the floor of the original tub and the floor of the newly inserted tub. Still another prior art system requires the use of exotic bathtub structures which substantially preclude modification of an existing bathtub structure and thus significantly increases the cost of the overall system. Still an additional prior art system utilizes a special air bubble-generating mat that must be manually placed inside the bathtub each time the system is to be used, thereby reducing the comfort and convenience of the hydromassage concept.
The use of expensive, specially constructed bathtubs and the use of very complicated hose manifold systems substantially increase the overall cost of installing an air bubble injection hydromassage system, commercially limiting the success of an otherwise advantageous, simple concept of injecting only air into a bathtub. In addition, a substantial, if not major portion of the market for such hydromassage systems resides in modification of existing bathtubs as opposed to installing new bathtubs. Many of the prior art systems available in Europe are simply incompatible with the concept of modifying an existing bathtub and those that are compatible require such extensive hose manifolds that it becomes prohibitively expensive to modify an existing bathtub even when it is physically possible to do so.
There is therefore a need for an air injection hydromassage system which exploits rather than defeats the lower-cost, simpler use of only air to inject into a bathtub to create the hydromassage effect. There is simultaneously a need for a system of that type which provides many of the advantages currently available in air and water venturi systems currently in use in the United States. Thus for example, it would be highly advantageous to also provide an air injection system which permits the user to vary the force of water activation on a jet-by-jet basis thereby permitting each user to modify the massage effect in accordance with his own personal preferences and the desire to massage one or more body parts to a greater extent than others.
The most relevant prior art known to the applicants is disclosed in U.K. Patent application No. 2,114,021A published Aug. 17, 1983. While this disclosure describes an air injection apparatus which solves some of the aforementioned needs, it suffers from two significant disadvantages to which the present invention is directed. First and foremost, the aforementioned in U.K. patent application discloses system which requires a substantial vertical space beneath the floor of the tub to interconnect a plurality of nozzle assemblies. Secondly, the disclosed system fails to provide any means for permitting the user to control the force and direction of air flow out of the nozzles and into the bathtub.
Other relevant prior art includes the following British patents:
1,224,308 Jacuzzi PA1 1,460,206 Jacuzzi PA1 1,496,613 Kulisch PA1 1,604,587 May PA1 2,026,317A Dupont PA1 2,107,180A Price et al PA1 2,114,021A Randle PA1 2,120,546A Carr PA1 2,159,404A Brueton PA1 2,161,072A Brueton PA1 2,169,799A Tennant